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    <title>Document</title>
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<body>
    <script>
        function getRandom(min,max){
            return Math.floor(Math.random() * (max - min +1)) + min;
        }
        var random = getRandom(1,50);
        
        for(var i = 10;i>=1;i--){
            var num = prompt('请输入你要猜的数字');
            if(num > random){
                alert('你猜大了还有'+i+'机会');
            } else if(num < random){
                alert('你猜小了还有'+i+'机会');
            } else{
                alert('你猜对了');
                break;
            }
        }
    </script>
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